They worked pretty well with the HD 650 and have great connectivity options.

As others have stated though, the 650 only gets better & better when you spend more on the amp. Buying two separate units as I've linked to above would allow you to trade the O2 amp at a later date for something better whilst still holding on to the ODAC for your source.

Member of the Trade: top-headphone

Hi mates..i have sennheiser hd650 and i want a good desktop dac/amp for it..and i only can buy from chinese brand..what is your seggestion? I have chord mojo but i feel isnt enough at all..my budget is 350us $ Thanks for your help

500+ Head-Fier

Hi mates..i have sennheiser hd650 and i want a good desktop dac/amp for it..and i only can buy from chinese brand..what is your seggestion? I have chord mojo but i feel isnt enough at all..my budget is 350us $ Thanks for your help

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you do realize the thread is 2 years old?....350 get you a used Schiit stack

100+ Head-Fier

Hi mates..i have sennheiser hd650 and i want a good desktop dac/amp for it..and i only can buy from chinese brand..what is your seggestion? I have chord mojo but i feel isnt enough at all..my budget is 350us $ Thanks for your help

Click to expand...

Check out the nfb11.28 vs r2r thread. The end game for all mid fi amp dacs, and for a portable solution maybe the iDSD Black Edition. This combo sounds really good. Vocals really come forward at max power and sounds pop out of nowhere, in a good way, I often turn and look around Wondering if there's a speaker somewhere in the room.